Patterned chemical bath deposition of a textured thin film from a printed seed layer

Abstract

A chemical bath deposition (CBD) process is provided for forming a textured zinc oxide film pattern from a zinc oxide printed seed layer. The process provides a substrate and prints a zinc oxide seed layer in a pattern overlying the substrate. Using a CBD process, a textured zinc oxide film is grown overlying the zinc oxide seed layer pattern, where the textured zinc oxide film has a variation in film thickness of greater than 200 nanometers (nm). In one aspect, growing the textured zinc oxide film includes: preparing a ZnO precursor bath; maintaining a bath temperature of about 70 degrees C.; and, leaving the substrate in the bath for about an hour. In another aspect, growing the textured zinc oxide film includes forming a textured zinc oxide film with zinc oxide crystals having a pyramidal shape with a height of greater than 200 nm.

1. A chemical bath deposition (CBD) process for forming a textured film from a metal oxide printed seed layer, the process comprising:
 providing a substrate; 
 forming a first metal oxide seed layer in a pattern overlying the substrate as follows
 preparing a first metal oxide precursor solution; 
 printing the first metal oxide precursor solution in a pattern on the substrate; 
 annealing the first metal oxide precursor solution; and, 
 
 using a CBD process, forming a textured film overlying the first metal oxide seed layer pattern. 
 
     
     
       2. The process of  claim 1  wherein printing the first metal oxide precursor includes using a printing process selected from a group consisting of piezoelectric inkjet, thermal inkjet, gravure, offset, microcontact printing, and screen printing. 
     
     
       3. The process of  claim 1  wherein forming the textured film includes:
 preparing a second metal oxide precursor bath; 
 immersing the substrate in the second metal oxide precursor bath; and, 
 growing a textured second metal oxide film in the pattern from the first metal oxide seed layer. 
 
     
     
       4. The process of  claim 3  wherein the metal in the first and second oxides is the same metal. 
     
     
       5. The process of  claim 3  wherein the metals in the first and second oxides are different metals. 
     
     
       6. The process of  claim 3  wherein growing the textured second oxide film includes growing a textured ZnO film. 
     
     
       7. The process of  claim 6  wherein preparing the second metal oxide precursor bath includes preparing a ZnO precursor bath as follows:
 creating a mixture of water and ethanol; and, 
 dissolving a zinc salt and methenamine in the mixture. 
 
     
     
       8. The princess of  claim 7  wherein immersing the substrate in the second metal oxide precursor bath includes maintaining the ZnO precursor bath at a temperature of about degrees C.; and,
 wherein growing the textured ZnO film in the pattern includes leaving the substrate in the bath for about an hour. 
 
     
     
       9. The process of  claim 7  wherein dissolving the zinc salt and methenamine in the mixture includes dissolving a zinc salt selected from a group consisting of zinc acetate, zinc nitrate, and zinc chloride. 
     
     
       10. The process of  claim 1  wherein forming the first metal oxide seed layer includes forming a ZnO seed layer. 
     
     
       11. The process of  claim 10  wherein preparing the first metal oxide precursor solution includes preparing a ZnO seed layer precursor solution as follows:
 dissolving zinc acetate in a solution of ethanol and monoethanolamine; and, 
 stirring. 
 
     
     
       12. The process of  claim 11  wherein annealing the first metal oxide precursor solution includes annealing the ZnO precursor solution at a temperature of about 450 degrees C. for about 30 minutes. 
     
     
       13. The process of  claim 1  wherein providing the substrate includes providing the substrate selected from a group consisting of soda-lime glass, borosilicate glass, silicon, and thermal oxide of silicon. 
     
     
       14. The process of  claim 1  wherein forming the textured film overlying the first metal oxide seed layer pattern includes forming a textured film with crystals having a pyramidal shape with a height of greater than 200 nanometers. 
     
     
       15. The process of  claim 1  wherein forming the textured film includes:
 preparing a metal chalcogenide precursor bath; 
 immersing the substrate in the metal chalcogenide precursor bath; and, 
 growing a textured metal chalcogenide film in the pattern from the first metal oxide seed layer. 
 
     
     
       16. A chemical bath deposition (CBD) process for forming a textured zinc oxide film pattern from a zinc oxide printed seed layer, the process comprising:
 providing a substrate; 
 printing a zinc oxide seed layer in a pattern overlying the substrate; and, 
 using a CBD process, growing a textured zinc oxide film overlying the zinc oxide seed layer pattern, where the textured zinc oxide film has a variation in film thickness of greater than 200 nanometers. 
 
     
     
       17. The process of  claim 16  wherein growing the textured zinc oxide film includes:
 preparing a ZnO precursor bath; 
 maintaining a bath temperature of about 70 degrees C.; and, 
 leaving the substrate in the bath for about an hour. 
 
     
     
       18. The process of  claim 16  wherein growing the textured zinc oxide film includes forming a textured zinc oxide film with zinc oxide crystals having a pyramidal shape with a height of greater than 200 nanometers. 
     
     
       19. A chemical bath deposition (CBD) process for forming a textured film pattern from a metal oxide printed seed layer, the process comprising:
 providing a substrate; 
 forming a first metal oxide seed layer in a pattern overlying the substrate; and, 
 using a CBD process, forming a textured film overlying the first metal oxide seed layer pattern as follows:
 preparing a metal chalcogenide precursor bath; 
 immersing the substrate in the metal chalcogenide precursor bath; and, 
 growing a textured metal chalcogenide film in the pattern from the first metal oxide seed layer. 
 
 
     
     
       20. A chemical bath deposition (CBD) process for forming a textured film pattern from a metal oxide printed seed layer, the process comprising:
 providing a substrate; 
 forming a first metal oxide seed layer in a pattern overlying the substrate; and, 
 using a CBD process, forming a textured film with crystals having a pyramidal shape and a height of greater than 200 nanometers, overlying the first metal oxide seed layer pattern.